Minolta Camera Kabushiki Kaisha

Minolta Company, Ltd.

Minolta Camera Co., Ltd.

Itaru Saito

Ken Matsubara

Tomohiko Masuda

Hirohisa Kitano

Kouichi Shingaki

Kenichi Wada

Tsukasa Yagi

Yuji Kamoda

Isao Doi

Atsushi Fujita

Koji Wakamiya

Yuji Enoguchi

Hiroshisa Kitano

A method for driving an optical write device, in which a time for formation of a pixel is divided into a plurality of periods, and tone level control based on multi-tone image, data is performed in each of the periods. For example, the time for formation of a pixel is divided by applying a train of pulses with widths weighted in the ratio of 4:2.1, and in each duration of the pulses, a clock signal for 64 tone levels is given.

Method for driving an optical write device

In a light shutter device in which multiple light shutter elements are located on a substrate made of PLZT, and the ON/OFF control of light is carried out by having an electrical field operate on each light shutter element from a pair of electrodes, the cross-talk phenomenon occurs among adjacent elements on the PLZT substrate, i.e., the elements ( ), ( ) and ( ). In order to effectively prevent such cross-talk, driving is carried out such that an electrical field does not operate on such elements simultaneously as a practical matter. In other words, the one line cycle is divided into periods (a) and (b), and the element ( ) is turned ON during the period (a) while the other elements ( ) and ( ) are turned ON during the period (b). Through this operation, a light shutter device in which each element has a stable amount of pass-through light may be obtained.

Light shutter device

A light shutter device which has a plurality of light transmitting portions (light shutter elements) on a planar PLZT substrate. By applying voltages between a common electrode and individual electrodes to apply electric fields to the light shutter elements, the light shutter elements transmit and shut light individually. Suppose each of the individual electrodes faces the common electrode at a distance L and has a dimension W in a direction perpendicular to the direction of electric field, W/L>2. Suppose each of the individual electrodes has a dimension D in the direction of electric field, preferably D/L>0.5. Further, the individual electrodes are so placed that the distance between a side of one light shutter element which extends in a direction perpendicular to the direction of electric field and each of the individual electrodes which drive the other light shutter elements is not less than 5L.

An image forming apparatus which is capable of composing an image with a high accuracy on an image receiving member with use of a plurality of light signal emitting heads. The image forming apparatus, which is used for forming an image on the image receiving member such as a photographic paper or a electrophotographic photosensitive member. Each light signal emitting head turns on and off a plurality of light signal emitting elements extending in a main scanning direction in accordance with image data. The image receiving member is guided by a cylindrical guide roller with being adhered to the curving section of the guide roller at an exposure position. The light emergent from each light signal emitting head is changed its optical path at a dichroic prism or a half mirror and exposes the image receiving member linearly.

Image forming apparatus provided with a plurality of light signal emitting heads

A method for measuring the quantity of light emitted from an optical write head which drives an array of light shutter elements extending in a main scanning direction individually in accordance with image data. In order to measure the quantity of light outputted from each of the light shutter elements, a photosensor is moved in the main scanning direction at a constant speed while the light shutter elements are driven in such a way that adjacent elements are not driven at a time. While light shutter elements which are in odd numbers in the array are driven, the photosensor is moved forward to measure the quantities of light outputted therefrom, and while light shutter elements which are in even numbers in the array are driven, the photosensor is moved backward to measure the quantities of light outputted therefrom. The optical write head is employed in a printer together with a light-quantity measuring unit for the optical write head, so that light-quantity measurement and production of light-quantity correction data are possible at real time.

Method for measuring the quantity of light emergent from an optical tip array and image forming apparatus provided with an optical tip array

Disclosed is a light shutter device comprising a plurality of optical element for modulating light passing therethrough. Each optical element is made of PLZT and the surface of a light modulating region of each optical element is coated with a thin film. The surface electrical resistance on the thin film is 10.sup.10 .OMEGA./sq or less.

Optical element and light shutter device using the same

An optical shutter device for use, e.g., in an optical printer includes a plurality of electrooptic chips each having a plurality of very small segments for optical modulation. The optical shutter device has a voltage adjusting circuit which individually supplies the driving voltage to the chips depending on the light transmitting characteristics intrinsic to the chips. Thus, even when the chips have different light transmitting characteristics, the image produced by the chips will have a uniform intensity.

Optical shutter device

A method and device for driving an electro-optical light shutter array including a plurality of shutter elements each having an electro-optical effect to polarize an incident light by setting up an electric field. The device includes a plurality of individual electrodes provided on the respective shutter elements and a common electrode provided on the respective shutter elements electrically in common. A square pulse is applied to the arbitrary individual electrode while a triangular pulse is applied to the common electrode to set up an electric field of which an intensity continuously varies within one driving period. Moreover, an alternating electric field may be set up in the electro-optical light shutter array in a recovery period. In this case, a first light amount when the positive electric field is set up and a second light amount when the negative electric field is set up are detected. A recovery operation is carried out until the first and second light amounts become substantially equal with each other.

Method and device for driving electro-optical light shutter

A light printer with a light shutter having an array of electro-optical elements is disclosed. The light printer provides with a detection circuit for monitoring temperature and/or time dependent variations regarding the electro-optical elements of the light shutter and a driving voltage control circuit for controlling an optimum driving voltage of the light shutter according to results detected by the detection circuit.

Light printer with photoelectric light quantity control means

A method of and a device for driving a light shutter having an electrooptical effect to polarize an incident light by applying an electric field to the light shutter. When the light shutter is made activate, an excessive electric field in addition to a half-wave electric field which is a specific one to polarize an incident light at 90.degree. in the static characteristics of the light shutter is applied to the light shutter initially, and subsequently, the half-wave electric field only is applied to the light shutter. To discharge the electric charge accumulated in the light shutter, no voltage is applied to electrodes each of which is provided on the wall of the light shutter so as to oppose each other subsequent to the application of the electric field until the next application thereof.

Method and device for driving electrooptical light shutter

A method of driving an electro-optical light shutter for use in a recording apparatus. According to the method, an electric field of a predetermined direction is applied to the light shutter during a recording period and a further electric field having a direction opposite to the predetermined direction is applied to the light shutter during a waiting period.

Method of driving electro-optical light shutter for use in recording

A display apparatus comprising a modulator sandwiched between two polarizers. The modulator includes a plurality of light transmitting windows arranged in a matrix on a substrate having an electrooptical effect. Each window is associated with an electrode pair for forming an electric field across the window. One scanning line electrically interconnects first electrodes in the electrode pairs of the windows arranged in a row. One signal line electrically interconnects second electrodes in the electrode pairs of the windows arranged in a column. A scanning circuit sequentially and individually electrifies the scanning lines. A signal circuit is operable in response to a synchronizing signal received from the scanning circuit and display information for electrifying one of the signal lines connected to the electrode pair of a selected window for forming an electric field. An electric field control circuit provides zero potential difference in the electrode pairs of the other windows than the selected window.

Display apparatus

A light shutter means with a plurality of shutter elements formed of an electro-optical material, the elements being defined independently and three-dimensionally on an upper face of a substantially polyhedral chip and aligned in at least two arrays. Each shutter element has a shutter window for selective light transmission therethrough. A common electrode for the shutter elements extends over opposing faces of the shutter element arrays and to at least one side face of the chip. Each opposing pair of the elements in the one array and in the other array are disposed such that their shutter windows are overlapped with each other as viewed from a direction normal to the direction of element array extension on the chip's upper face.

Light shutter arrays for forming images

A recording apparatus comprising a copying system for projecting the image of an original document onto a photosensitive member to form an electrostatic latent image thereon, and a printing system for forming an electrostatic latent image on the photosensitive member in response to image information received from a data processing machine. This recording apparatus is operable in a printing mode and a copying mode. In the printing mode, recording paper carrying an image printed in accordance with the image information is either discharged outwardly of the recording apparatus or forwarded to an automatic document feeder to serve as an original document or documents. In the copying mode, the or each original document is copied a selected number of times as in any conventional copying machine.

Growing community of inventors

Osaka, Japan

Itaru Saito