Patent US4634226A successfully refreshed from Google Patents.
US4634226A
Expired / Lapsed
US
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Optical apparatus using ferroelectric liquid crystal and switching unit for emitted light
Assignee: Hitachi Ltd
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Filing: 1984-04-06
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Granted: 1987-01-06
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Expires: 2004-04-06
Abstract
Abstract An optical apparatus comprises an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces. The optically functional material has such a characteristic that intensity of light issuing from the optical device changes asymmetrically in response to inversion of the polarity of an applied external field. Pulse voltages of one polarity for determining the intensity of the issuing light and pulse voltages of an opposite polarity are applied from a source at a predetermined period so that an average voltage is zeroed within the predetermied period. The issuing light intensity under the application of the pulse voltages of one polarity and the issuing light intensity under the application of the other pulse voltages are selected or changed by a switching unit.
Inventors
- 👤 Masato Isogai
- 👤 Shintaroo Hattori
- 👤 Kishiro Iwaskai
- 👤 Akio Mukoh
- 👤 Takao Umeda
- 👤 Yoshiharu Nagae
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:56
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/133; G02F1/13306; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
134 words
An optical apparatus comprising an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces, said optically functional material having such a characteristic that intensity of light emitted from said optical device changes asymmetrically in response to inversion of the polarity of an applied external field, wherein first means for applying to said optically functional material pulse voltages of one polarity for determining the intensity of the emitted light and pulse voltages of an opposite polarity at a predetermined period so that an average voltage is zeroed within the predetermined period, and second means for selecting or changing said emitted light intensity under the application of the pulse voltages of one polarity and said emitted light intensity under the application of the other pulse voltages.
Claim 2
Dependent Claim
134 words
An optical apparatus comprising an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces, said optically functional material having such a characteristic that intensity of light emitted from said optical device changes asymmetrically in response to inversion of the polarity of an applied external field, wherein first means for applying to said optically functional material pulse voltages of one polarity for determining the intensity of the emitted light and pulse voltages of an opposite polarity at a predetermined period so that an average voltage is zeroed within the predetermined period, and second means for selecting or changing said emitted light intensity under the application of the pulse voltages of one polarity and said emitted light intensity under the application of the other pulse voltages.
Claim 3
Dependent Claim
16 words
An optical apparatus according to claim 1, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 4
Dependent Claim
17 words
An optical apparatus according to claim 2, wherein said optical device comprises a light transmission type device.
Claim 5
Dependent Claim
16 words
An optical apparatus according to claim 3, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 6
Dependent Claim
49 words
An optical apparatus according to claim 1, wherein said second means comprises a unit arranged on a path of light passing through said optical device and having a function to intermittently block the light, and the intermittent blocking of light is synchronized with the application of said pulse voltages.
Claim 7
Dependent Claim
16 words
An optical apparatus according to claim 5, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 8
Dependent Claim
17 words
An optical apparatus according to claim 5, wherein said optical device comprises a light transmission type device.
Claim 9
Dependent Claim
17 words
An optical apparatus according to claim 7, wherein said chopper comprises a pleochroic ferroelectric liquid crystal device.
Claim 10
Dependent Claim
19 words
An optical device according to claim 7, wherein said chopper comprises a rotary member formed with light transmission ports.
Claim 11
Dependent Claim
16 words
An optical apparatus according to claim 7, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 12
Dependent Claim
65 words
An optical apparatus according to claim 1, wherein said first means comprises means for making sufficiently shorter an application time interval of said pulse voltages of one polarity than that of said pulse voltages of an opposite polarity signal within said predetermined period and for making sufficiently larger an absolute value of a pulse height of said pulse voltage than that of said voltage signal.
Claim 13
Dependent Claim
16 words
An optical apparatus according to claim 11, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 14
Dependent Claim
67 words
An optical apparatus according to claim 12, wherein said chopper synchronizes the application of said pulse voltages of one polarity with the passage of light to establish a bright state of transmission light and synchronizes the application of said pulse voltages of one polarity with the intermittent blocking of the light path to establish a dark state of transmission light, thereby switching the bright and dark states.
Claim 15
Dependent Claim
53 words
An optical apparatus according to claim 12, wherein said chopper synchronizes the timing for the application of said pulse voltage of one polarity and the timing for the passage of light in said a manner that these timings partly overlap, thereby providing a tonal state of transmission light issuing from said optical device.
Claim 16
Dependent Claim
17 words
An optical apparatus according to claim 12, wherein said chopper comprises a pleochroic ferroelectric liquid crystal device.
Claim 17
Dependent Claim
19 words
An optical device according to claim 12, wherein said chopper comprises a rotary member formed with light transmission ports.
Claim 18
Dependent Claim
16 words
An optical apparatus according to claim 12, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 19
Dependent Claim
17 words
An optical apparatus according to claim 11, wherein said optical device comprises a light transmission type device.
Claim 20
Dependent Claim
16 words
An optical apparatus according to claim 18, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 21
Dependent Claim
17 words
An optical apparatus according to claim 1, wherein said optical device comprises a light transmission type device.
Claim 22
Dependent Claim
19 words
An optical device according to claim 20, wherein said chopper comprises a rotary member formed with light transmission ports.
Claim 23
Dependent Claim
16 words
An optical apparatus according to claim 20, wherein said optically functional material comprises ferroelectric liquid crystal.
Claim 24
Dependent Claim
17 words
An optical apparatus according to claim 20, wherein said chopper comprises a pleochroic ferroelectric liquid crystal device.
Claim 25
Dependent Claim
145 words
In an optical apparatus comprising an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces, said optically functional material having such a characteristic that intensity of light issuing from the optical device changes asymmetrically in response to inversion of the polarity of an applied external field, the improvement which comprises: first means for applying to said optically functional material pulse voltages of one polarity for determining the intensity of the issuing light and pulse voltages of an opposite polarity at a predetermined period so that an average voltage is zeroed within the predetermined period; and a chopper arranged on a path of light passing through said optical device and having a function to intermittently block the light and to synchronize the intermittent blocking of light with the application of said pulse voltages of one polarity.
Claim 26
Dependent Claim
145 words
In an optical apparatus comprising an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces, said optically functional material having such a characteristic that intensity of light issuing from the optical device changes asymmetrically in response to inversion of the polarity of an applied external field, the improvement which comprises: first means for applying to said optically functional material pulse voltages of one polarity for determining the intensity of the issuing light and pulse voltages of an opposite polarity at a predetermined period so that an average voltage is zeroed within the predetermined period; and a chopper arranged on a path of light passing through said optical device and having a function to intermittently block the light and to synchronize the intermittent blocking of light with the application of said pulse voltages of one polarity.
Claim 27
Dependent Claim
38 words
An optical apparatus according to claim 24, wherein said ferroelectric liquid crystal is so aligned that its helical axis direction is aligned in a priority direction which is substantially parallel to the surface of each of said substrates.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |