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US4671616A Expired / Lapsed US ⏱️ 0.0 years remaining

Diagonally offset, dielectric anisotropy inversion, liquid crystal, microshutters

Assignee: Seiko Epson Corp
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Filing: 1986-03-10
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Granted: 1987-06-09
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Expires: 2006-03-10
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Abstract

Abstract A liquid crystal optical device including a plurality of optical shutters is provided. The optical device includes a first glass substrate having N common electrodes disposed thereon and a second glass substrate having N signal electrodes disposed thereon, the glass substrates spaced apart and opposed to each other so that the electrodes are crossed. A liquid crystal material including a nematic liquid crystal having dielectric anisotropy which becomes 0 at a crossing frequency (fC) of 100 KHz or below at atmospheric temperatures including a optically active material encapsulated between the glass substrates. Polarizing plates are disposed on the outside of the liquid crystal panel and the device is driven in a N time-sharing mode by applying the driving signals to the common electrode and the signal electrodes. The optical device is particularly well suited for use in an optical printer in view of the rapid response times.

Inventors

  • 👤 Kenji Aoki
  • 👤 Katsumori Takei
  • 👤 Haruo Nakamura
  • 👤 Yoshikazu Matsushita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 16:56
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/1313; G02F1/133; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1238; G06K15/1242; G06K15/1252

Claims Analysis

Total Claims: 40
Claim 1
Independent Claim 318 words
A liquid crystal optical device for operating in a time-sharing driving method, comprising: a liquid crystal cell formed from a first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters, and a second cooperating transparent plate having M coooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein both N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from each other with respect to the crossed electrodes and said transparent regions repeat along the common electrode strips at each crossing signal electrode; a liquid crystal composition encapsulated in the space between the transparent plates being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C ; two polarizing plates disposed on the outer surfaces of the transparent plates of the cell; and time-sharing liquid crystal driving circuit means coupled to said N common and M signal electrodes for generating time-sharing drive signals to be applied to said electrodes for driving the device in an N time-sharing driving method whereby light is selectively transmitted through the transparent regions of the common electrodes in response to the drive signals.
Claim 2
Dependent Claim 318 words
A liquid crystal optical device for operating in a time-sharing driving method, comprising: a liquid crystal cell formed from a first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters, and a second cooperating transparent plate having M coooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein both N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from each other with respect to the crossed electrodes and said transparent regions repeat along the common electrode strips at each crossing signal electrode; a liquid crystal composition encapsulated in the space between the transparent plates being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C ; two polarizing plates disposed on the outer surfaces of the transparent plates of the cell; and time-sharing liquid crystal driving circuit means coupled to said N common and M signal electrodes for generating time-sharing drive signals to be applied to said electrodes for driving the device in an N time-sharing driving method whereby light is selectively transmitted through the transparent regions of the common electrodes in response to the drive signals.
Claim 3
Dependent Claim 63 words
The liquid crystal optical device of claim 1, wherein said N time-sharing driving circuit means is adapted to generate signals for defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f , and signals for optically switching, said signal for optically switching applied within the time assigned for writing T a .
Claim 4
Dependent Claim 31 words
The liquid crystal optical device of claim 2, wherein the signal for optically switching applied within the time assigned for writing T a includes a low frequency signal (f L ).
Claim 5
Dependent Claim 70 words
The liquid crystal optical device of claim 1, wherein the signals applied to the common electrode includes both a high frequency component (f H ) and a low frequency component (f L ) applied during said time assigned for writing T a , and a low frequency component (f L ) applied during remaining time of the writing period T f , a non-assigned time for writing ("T b ").
Claim 6
Dependent Claim 87 words
The liquid crystal optical device of claim 4, wherein said signals applied to the signal electrode is one of a first type which includes a high frequency component (f H ) out of phase with the high frequency component applied to the common electrode and a low frequency component opposite in phase to the low frequency component applied to the common electrode and a second type of a low frequency signal opposite in phase to the low frequency component of the signal applied to the common electrode.
Claim 7
Dependent Claim 57 words
The liquid crystal optical device of claim 1, in a high printing device further including a light source and a photosensitive surface on the opposite side of the cell for receiving light transmitted through the cell, said cell having a plurality of aperatures for selectively transmitting light therethrough in response to said signals applied to the cell.
Claim 8
Dependent Claim 78 words
The liquid crystal optical device of claim 6, wherein said plurality of aperatures in the liquid crystal cell are disposed in zig-zag fashion substantially along a line transverse to the direction of transfer to the photo-sensitive surface with intervals of L=(m+1/N)×vT f between the centers of adjacent transparent regions of adjacent common electrodes, wherein v is the transfering speed of the photo-sensitive surface and T 1 is the period of time for writing and m is an integer.
Claim 9
Dependent Claim 27 words
The liquid crystal optical device of claim 7, wherein said N time-sharing driving circuit means includes means for delaying signals by a time of m·T f .
Claim 10
Dependent Claim 19 words
The liquid crystal device of claim 1, wherein the gap between adjacent common electrodes is less than 20 μm.
Claim 11
Dependent Claim 35 words
The liquid crystal optical device of claim 1, including at least two common electrodes having a gap therebetween, and the transparent signal electrodes are formed with an opaque portion in the region overlapping the gap.
Claim 12
Dependent Claim 34 words
The liquid crystal optical device of claim 10, wherein the signal electrodes in the region away from the micro-shutter regions are formed of a metallic material to reduce the impedence of the signal electrodes.
Claim 13
Dependent Claim 37 words
The liquid crystal optical device of claim 10, wherein the common electrodes are disposed on the first transparent plate so that the aperatures formed on adjacent common electrode are alternately disposed on each side of the gap.
Claim 14
Dependent Claim 41 words
The liquid crystal optical device of claim 12, wherein said signal electrodes are off-set at the opaque region crossing the gap so that the two adjacent micro-shutter region on opposite sides of the gap are overlapped by the same signal electrode.
Claim 15
Dependent Claim 388 words
A light printing device, comprising a light signal generator including a light source, a liquid crystal light valve in the light path of the source of light, a liquid crystal driving circuit for selectively driving said light valve, a photo-sensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photo-sensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque strips and spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters, and a second cooperating transparent plate having M signal electrodes disposed on the interior surface thereof, substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes wherein N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from eachother with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each crossing signal electrode, a liquid crystal composition encapsulated in the space between the transparent plate being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the panel and said liquid crystal driving circuit being a time-sharing driving circuit means coupled to said N common and M signal electrodes for generating time-sharing drive signals to be applied to the electrodes for driving the light valve in an N time-sharing driving method whereby light is selectively transmitted through the transparent regions of the common electrodes in response to the drive signals.
Claim 16
Dependent Claim 388 words
A light printing device, comprising a light signal generator including a light source, a liquid crystal light valve in the light path of the source of light, a liquid crystal driving circuit for selectively driving said light valve, a photo-sensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photo-sensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque strips and spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters, and a second cooperating transparent plate having M signal electrodes disposed on the interior surface thereof, substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes wherein N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from eachother with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each crossing signal electrode, a liquid crystal composition encapsulated in the space between the transparent plate being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the panel and said liquid crystal driving circuit being a time-sharing driving circuit means coupled to said N common and M signal electrodes for generating time-sharing drive signals to be applied to the electrodes for driving the light valve in an N time-sharing driving method whereby light is selectively transmitted through the transparent regions of the common electrodes in response to the drive signals.
Claim 17
Dependent Claim 62 words
The light printing device of claim 13, wherein said N time-sharing driving circuit means is adapted to generate signals for defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f , and signals for optically switching, said signal for optically switching applied within the time assigned for writing T a .
Claim 18
Dependent Claim 30 words
The light printing device of claim 15, wherein the signal for optically switching applied within the time assigned for writing T a includes a low frequency signal (f L ).
Claim 19
Dependent Claim 69 words
The light printing device of claim 14, wherein the signals applied to the common electrode includes both a high frequency compnenet (f H ) and a low frequency component (f L ) applied during said time assigned for writing T a , and a low frequency component (f L ) applied during remaining time of the writing period T f , a non-assigned time for writing ("T b ").
Claim 20
Dependent Claim 108 words
The light printing device of claim 17, wherein said signals applied to the signal electrode is one of a first type which includes a high frequency component (f H ) out of phase with the high frequency component applied to the common electrode and a low frequency component opposite in phase to the low frequency componenet applied to the common electrode and a second type of a low frequency signal opposite in phase to the low frequency component applied to the common electrode and a second type of a low frequency signal oppostie in phase to the low frequency component of the signal applied to the common electrode.
Claim 21
Dependent Claim 37 words
The light printing device of claim 14, in a high printing device wherein said liquid crystal light valve includes a plurality of apertures for selectively transmitting light therethrough in response to said signals applied to the cell.
Claim 22
Dependent Claim 72 words
The light printing device of claim 19, wherein said plurality of aperatures in the liquid crytal cell are disposed in zig-zag fashion substantially along a line transverse to the direction of transfer to the photo-sensitive surface with intervals of L=(m+1/N)×vT f between the centers of adjacent micro-shutters wherein v is the transfering speed of the photo-sensitive surface and T f is the period of time for writing, and m is an integer.
Claim 23
Dependent Claim 26 words
The light printing device of claim 20, wherein said N time-sharing driving circuit mean includes means for delaying signals by a time of M·T 1 .
Claim 24
Dependent Claim 34 words
The light printing device of claim 14, including at least two common electrodes having a gap therebetween, and the transparent signal electrodes are formed with an opaque portion in the region overlapping the gap.
Claim 25
Dependent Claim 33 words
The light printing device of claim 22, wherein the signal electrodes in the region away from the micro-shutter regions are formed of a metallic material to reduce the impedence of the signal electrodes.
Claim 26
Dependent Claim 36 words
The light printing device of claim 22, wherein the common electrodes are disposed on the first transparent plate so that the aperatures formed on adjacent common electrodes are alternately disposed on each side of the gap.
Claim 27
Dependent Claim 40 words
The light printing device of claim 24, wherein said signal electrodes are off-set at the opaque region crossing the gap so that the two adjacent micro-shutter region on opposite sides of the gap are overlapped by the same signal electrode.
Claim 28
Independent Claim 328 words
A method for driving a liquid crystal optical device in a time-sharing driving method, the device including a liquid crystal cell formed from a first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters and a second transparent plate having M cooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein both N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally offset from each other with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each signal electrode, a liquid crystal composition encapsulated in the space between the transparent plates being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the cell, comprising: applying to said common and signal electrodes time-sharing drive signals for driving the device in an N time-sharing driving method, said signals defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f and for optically switching, said signal for optically switching the micro-shutter applied within the time assigned for writing T a .
Claim 29
Independent Claim 328 words
A method for driving a liquid crystal optical device in a time-sharing driving method, the device including a liquid crystal cell formed from a first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters and a second transparent plate having M cooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein both N and M are integers greater than or equal to two, said transparent plates spaced apart from and substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally offset from each other with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each signal electrode, a liquid crystal composition encapsulated in the space between the transparent plates being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotropy is 0 and positive low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the cell, comprising: applying to said common and signal electrodes time-sharing drive signals for driving the device in an N time-sharing driving method, said signals defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f and for optically switching, said signal for optically switching the micro-shutter applied within the time assigned for writing T a .
Claim 30
Dependent Claim 27 words
The method of claim 26, wherein the signal for optically switching within the time assigned for writing T a includes a low frequency signal (f L ).
Claim 31
Dependent Claim 67 words
The method of claim 26, wherein the signals applied to the common electrode include both a high frequency component (f H ) and a low frequency component (f L ) applied during said time assigned for writing T a , and a low frequency component (f L ) applied during remaining time of the writing period T f , a non-assigned time for writing ("T b ").
Claim 32
Dependent Claim 84 words
The method of claim 28, wherein said signals applied to the signal electrode is one of a first type which includes a high frequency component (f H ) out of phase with the high frequency component applied to the common electrode and a low frequency component opposite in phase to the low frequency component applied to the common electrode and a second type of a low frequency signal opposite in phase to the low freqency component of the signal applied to the common electrode.
Claim 33
Independent Claim 397 words
A method of printing utilizing a light printing device including light signal generator including a light source, a liquid crystal light valve in the light path of the source of light, a liquid crystal driving circuit for selectively driving said light valve, a photo-sensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photo-sensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters and a second transparent plate having M cooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein N and M are integers greater than or equal to two, said transparent plates spaced apart from said substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from each other with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each crossing signal electrode, a liquid crystal composition encapsulated in the space between the transparent plate being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotroy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the panel, comprising applying to said common and signal electrodes time-sharing drive signals for driving the light valve in an N time-sharing driving method, said signals defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f and for optically switching, said signal for optically switching the micro-shutter applied within the time assigned for writing T a .
Claim 34
Independent Claim 397 words
A method of printing utilizing a light printing device including light signal generator including a light source, a liquid crystal light valve in the light path of the source of light, a liquid crystal driving circuit for selectively driving said light valve, a photo-sensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photo-sensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof said common electrodes being substantially opaque parallel strips spaced apart from each other, each strip having a plurality of M spaced transparent regions for forming light micro-shutters and a second transparent plate having M cooperating signal electrodes disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the transparent regions of the common electrodes, wherein N and M are integers greater than or equal to two, said transparent plates spaced apart from said substantially parallel to each other for forming a space therebetween and the plates disposed so that the respective electrodes cross in plan view, the transparent regions in adjacent common electrodes diagonally off-set from each other with respect to the crossed electrodes and said transparent regions repeating along the common electrode strips at each crossing signal electrode, a liquid crystal composition encapsulated in the space between the transparent plate being a nematic liquid crystal including an effective amount of an optically active material, the composition having a critical frequency ("f C ") of less than 100 KHz at ordinary temperatures wherein the dielectric anisotroy is 0 and positive at low frequencies ("f L ") lower than f C and negative at high frequencies ("f H ") higher than f C , two polarizing plates disposed on the outer surfaces of the transparent plates of the panel, comprising applying to said common and signal electrodes time-sharing drive signals for driving the light valve in an N time-sharing driving method, said signals defining a writing period ("T f "), N assigned times for writing ("T a ") within the writing period T f and for optically switching, said signal for optically switching the micro-shutter applied within the time assigned for writing T a .
Claim 35
Dependent Claim 278 words
A liquid crystal optical device for operating in a time-sharing manner, comprising: liquid crystal cell means formed from a first transparent plate means and a cooperating second transparent plate means; a plurality of N common electrode means disposed in spaced, parallel strips on the interior surface of the first transparent plate means to provide a plurality of M spaced regions for forming light micro-shutters; a plurality of M cooperating signal electrode means disposed on the interior of the second transparent plate means substantially orthogonal to the common electrode means and in registration with the micro-shutter forming regions thereof, both N and M being integers greater than or equal to two, the transparent plate means being spaced apart from and substantially parallel to each other for forming a space therebetween and the transparent plate means being disposed so that the respective electrode means cross in plan view; opaque means including transparent regions for defining micro-shutters located where the respective electrode means cross, there being M transparent regions diagonally offset from each other across the width of the common electrode means and with respect to the crossed electrode means, the transparent regions repeating along the common electrode means at each crossing signal electrode means; liquid crystal means encapsulated in the space between the transparent plate means; and time sharing liquid crystal driving circuit means coupled to the N common and M signal electrode means for applying signals to the electrode means which optically switch the light micro-shutters, the signals including a signal of low frequency f L within a period ("T f /N") where T f is a writing period, whereby transmission of light through the liquid crystal is stopped.
Claim 36
Dependent Claim 278 words
A liquid crystal optical device for operating in a time-sharing manner, comprising: liquid crystal cell means formed from a first transparent plate means and a cooperating second transparent plate means; a plurality of N common electrode means disposed in spaced, parallel strips on the interior surface of the first transparent plate means to provide a plurality of M spaced regions for forming light micro-shutters; a plurality of M cooperating signal electrode means disposed on the interior of the second transparent plate means substantially orthogonal to the common electrode means and in registration with the micro-shutter forming regions thereof, both N and M being integers greater than or equal to two, the transparent plate means being spaced apart from and substantially parallel to each other for forming a space therebetween and the transparent plate means being disposed so that the respective electrode means cross in plan view; opaque means including transparent regions for defining micro-shutters located where the respective electrode means cross, there being M transparent regions diagonally offset from each other across the width of the common electrode means and with respect to the crossed electrode means, the transparent regions repeating along the common electrode means at each crossing signal electrode means; liquid crystal means encapsulated in the space between the transparent plate means; and time sharing liquid crystal driving circuit means coupled to the N common and M signal electrode means for applying signals to the electrode means which optically switch the light micro-shutters, the signals including a signal of low frequency f L within a period ("T f /N") where T f is a writing period, whereby transmission of light through the liquid crystal is stopped.
Claim 37
Dependent Claim 19 words
The liquid crystal optical device of claim 31 in which the opaque means is one of the electrode means.
Claim 38
Dependent Claim 329 words
A light printing device, comprising a light signal generator including a light source, a liquid crystal light valve in the light path of the light source, a liquid crystal driving circuit for selectively driving the light valve, a photosensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photosensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, the common electrodes being strips which are spaced apart from each other, each strip providing a plurality of M spaced regions for forming light micro-shutters, the second transparent plate having a plurality of M cooperating signal electrode means disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the micro-shutter forming regions thereof, both N and M being integers greater than or equal to two, the transparent plates being spaced apart from and substantially parallel to each other for forming a space therebetween and the plates being disposed so that the respective electrode means cross in plan view, opaque means including transparent regions for defining micro-shutters located where the respective electrodes cross, there being M transparent regions diagonally offset from each other across the width of the common electrodes and with respect to the crossed electrodes, the transparent regions repeating along the common electrodes at each crossing signal electrode, liquid crystal encapsulated in the space between the transparent plates, and a time sharing liquid crystal driving means coupled to said N common and M signal electrodes for applying signals to the electrodes which optically switch the light micro-shutters, the signals including a signal of low frequency f L within a period ("T f /N") where T f is a writing period, whereby transmission of light through the liquid crystal is stopped.
Claim 39
Dependent Claim 329 words
A light printing device, comprising a light signal generator including a light source, a liquid crystal light valve in the light path of the light source, a liquid crystal driving circuit for selectively driving the light valve, a photosensitive member for receiving light passing through the light valve, a developing section for developing an image formed by the light striking the photosensitive member, a transfer section and a fixing section, the liquid crystal light valve comprising a liquid crystal panel including two opposed transparent plates, the first transparent plate having a plurality of N common electrodes disposed on the interior surface thereof, the common electrodes being strips which are spaced apart from each other, each strip providing a plurality of M spaced regions for forming light micro-shutters, the second transparent plate having a plurality of M cooperating signal electrode means disposed on the interior surface thereof substantially orthogonal to the common electrodes and in registration with the micro-shutter forming regions thereof, both N and M being integers greater than or equal to two, the transparent plates being spaced apart from and substantially parallel to each other for forming a space therebetween and the plates being disposed so that the respective electrode means cross in plan view, opaque means including transparent regions for defining micro-shutters located where the respective electrodes cross, there being M transparent regions diagonally offset from each other across the width of the common electrodes and with respect to the crossed electrodes, the transparent regions repeating along the common electrodes at each crossing signal electrode, liquid crystal encapsulated in the space between the transparent plates, and a time sharing liquid crystal driving means coupled to said N common and M signal electrodes for applying signals to the electrodes which optically switch the light micro-shutters, the signals including a signal of low frequency f L within a period ("T f /N") where T f is a writing period, whereby transmission of light through the liquid crystal is stopped.
Claim 40
Dependent Claim 18 words
The liquid crystal optical device of claim 33 in which the opaque means is one of the electrodes.

References Cited (Backward Citations)

US4009934A Cited
US4236155A Cited
US4278328A Cited
US4297022A Cited
US4386836A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-08 1990-12-08 1991-06-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-08 1994-12-08 1995-06-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-08 1998-12-08 1999-06-09 $7700.00 Window Closed / Lapsed

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