Abstract: A method of driving a liquid crystal recording device comprises applying a drive signal to liquid crystal micro shutters defined at the intersection of common electrodes that are normal to signal electrodes. The drive signal is a signal experienced by a microshutter as a result of the application of a selected signal to the common electrode and the application of a recording signal to the signal electrode. Both the selected and recording signals contain components of frequencies grater and less than a specified frequency which causes the dielectric anistotropy of the liquid crystal to disappear. A drive signal which opens or closes microshutters for a selected period of time includes a signal whose frequency is lower than said specified frequency, and superposed waveform obtained when the signal whose frequency is loser than the specified frequency is superposed upon a signal whose frequency is higher than the specified frequency.

Abstract: A temperature control device uses a thermo-sensitive element to detect the temperature of an imaging system heated fixer device member. A comparator compares the potential generated by the thermo-sensitive element corresponding to the detected temperature with a reference voltage to set the temperature of the heated member to a predetermined level. A signal representing the comparison result is used for controlling the temperature of the heated member. Any abnormality of the heated member is detected on the basis of the output signal from an oscillator producing a signal which changes the reference potential at predetermined periods and from the comparator output signal.

Abstract: An apparatus for forming images is disclosed, in which a replaceable unit at least including a developing section is replaceably mounted in said apparatus body. Preliminary processing, such as developer agitation in said replaceable unit, is performed when a power source is connected and when the replaceable unit is mounted prior to an image formation operation. A timer started at the time of the connection of a power source is provided. A controller is provided to detect the output of the timer at the time of connection of the power source or at the time of the start of such an image formation operation for varying said preliminary processing according to the result of detection.

Abstract: A waveform forming device comprises a light source, a liquid crystal light shutter for passing or preventing the light of the light source and a driving circuit for driving a plurality of electrodes of the liquid crystal light shutter by using drive control signals including a signal of a high frequency f.sub.H and a signal of a low frequency f.sub.L. The frequencies f.sub.H and f.sub.L are respectively higher and lower than the frequency which makes a liquid crystal dielectric anisotropy zero. The waveform forming device has a ROM in which a plurality of basic control signals are stored, a counter for addressing a desired memory areas of the ROM and a waveform selector for selecting the basic control signals. The drive control signals are formed by combining the basic control signals, thereby to provide a desired drive pattern signal.

Abstract: A recording apparatus is capable recording information by light passed through the light shutter. When the information is recorded on to a sheet of paper, the recording apparatus controls that area on the paper where information is to be recorded, and it comprises plural AND or OR gates, counters and flip-flop circuits. The area on the paper where the information is to be recorded is indicated by an effective writing signal applied from a means located outside and recording data applied from a means located outside is recorded on to the sheet of paper responsive to this effective writing signal.

Abstract: In the recording apparatus of this invention, liquid crystal light shutter operates by using the double frequency drive. The double frequency drive utilizes signals of a high frequency f.sub.H and lower frequency f.sub.L. The dielectric anisotropy of liquid crystal matrial becomes positive in the case of the frequency f.sub.L lower than crossover frequency f.sub.C and becomes negative in the case of the frequency f.sub.H higher than the frequency f.sub.C. When the data signal including the signal of the frequency f.sub.L for a final period of a writing cycle Tw, is applied to write selection electrodes and data signal electrodes, liquid crystal light shutter is kept open for the final period of the writing cycle Tw, namely, opening or closing state of the shutter which is caused during a selection period can be eliminated.

Abstract: In a recording apparatus of this invention, liquid crystal light shutter operates by using the double frequency drive. The double frequency drive employs a higher frequency f.sub.H and lower frequency f.sub.L. The dielectric anisotropy becomes positive in the case of the lower frequency f.sub.L than crossover frequency f.sub.C and becomes negative in the case of the higher frequency f.sub.H than the frequency f.sub.C of liquid crystal material. The driver circuit of liquid crystal light shutter includes a delay circuit (146). Both a recording data delayed through the delay circuit (146) and a recording data formed without going through the delayed circuit (146) are produced in an LSI, to be supplied to write selecting electrodes and signal electrodes of the liquid crystal light shutter, thereby driving the liquid crystal light shutter in a time sharing manner.

Abstract: In accordance with the present invention, it has now been found that the coagulation property of polyurethane elastomers can be considerably improved without spoiling any desirable chemical property of the original elastomer, if polyurethane elastomers which are different only in N%, are mixed together in a specified range of mixing ratio or if a polyurethane elastomer is synthesized using a mixture of polymer glycols whose structural units are chemically the same, however, whose molecular weights are different from each other in a specified range, and a solution of the obtained elastomer is coagulated by a specified wet coagulation condition.