PROCEDURE AND ELECTRONIC CIRCUIT FOR CONTROLLING LCD OPTICAL SWITCHING ELEMENTS

• Main Authors: PIRS JANEZ, MARIN BOJAN, PIRS SILVIJA
• Format: Patent
• Language: English; Slovenian
• Published: 30.04.2000
• Edition: 7
• Subjects: BLASTING; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; ENGINEERING ELEMENTS AND UNITS; FREQUENCY-CHANGING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MECHANICAL ENGINEERING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SAFETY DEVICES IN GENERAL; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; THERMAL INSULATION IN GENERAL; WEAPONS

The application solves the problem of controlling LCD optic switching elements with alternating, rectangular electric signals with an amplitude that can change between several levels according to the current status. The changing of polarity of the control loops is supervised by an integrator, which integrates the voltage difference between the control electrodes of the LCD optical switching element in such a way that it retains the value of the time integral of the magnetic field within a predefined interval. Thus a complete elimination of long term direct current component of the electric control field for the LCD optical switching element is ensured regardless of the recurrence of changing or duration of individual electric control levels. Apart from that the electrical control signals in time are optionally provided with the possibility to equalise the potential on both electrodes at each modification of polarity of the electric control signals, which is far shorter than the LCD optic device switching time, thus allowing a spontaneous discharge of the electric capacity of the LCD optic switching element. By an appropriate selection of time it is possible to achieve an important reduction of power consumption required to control the LCD optic switching element. The application solves the problem of controlling LCD optic switching elements with alternating, rectangular electric signals with an amplitude that can change between several levels according to the current status. The changing of polarity of the control loops is supervised by an integrator, which integrates the voltage difference between the control electrodes of the LCD optical switching element in such a way that it retains the value of the time integral of the magnetic field within a predefined interval. Thus a complete elimination of long term direct current component of the electric control field for the LCD optical switching element is ensured regardless of the recurrence of changing or duration of individual electric control levels. Apart from that the electrical control signals in time are optionally provided with the possibility to equalise the potential on both electrodes at each modification of polarity of the electric control signals, which is far shorter than the LCD optic device switching time, thus allowing a spontaneous discharge of the electric capacity of the LCD optic switching element. By an appropriate selection of time it is possible to achieve an important reduction of power consumption required to control the LCD optic switching element. Patentna prijava rešuje problem krmiljenja LCD elektrooptičnih preklopnih elementov z izmeničnimi, pravokotnimi električnimi signali, katerih amplituda se v odvisnosti od trenutnega stanja lahko spreminja med več električnimi nivoji. Spreminjanje polaritete krmilnih električnih signalov nadzoruje integrator, ki integrira razliko napetosti na krmilnih elektrodah LCD elektrooptičnega preklopnega elementa tako, da ohranja vrednost časovnega integrala krmilnega električnega polja znotraj v naprej določenega intervala. S tem je zagotovljeno popolno izničenje dolgočasovne enosmerne komponente električnega krmilnega polja za LCD elektrooptični preklopni element ne glede na pogostost spreminjanja oziroma trajanja posameznih električnih krmilnih nivojev. Poleg tega je časovni potek električnih krmilnih signalov opcijsko zasnovan tako, da ob vsaki menjavi polaritete krmilnih električnih signalov za čas, ki je bistveno krajši od preklopnega časa LCD elektrooptičnega preklopnega elementa, izenači potencial na obeh krmilnih elektrodah in s tem omogoči spontano praznenje električne kapacitivnosti LCD elektrooptičnega preklopnega elementa. S primerno izbiro tega časa je mogoče doseči pomembno zmanjšanje porabe električne energije potrebne za krmiljenje LCD elektrooptičnega preklopnega elementa.ŕ