Self-scanned light-emitting device array, its driving method, and driving circuit
AssigneeFuji Xerox Co., Ltd.
InventorsSeiji Ohno, Shuya Ogi
Life of this patent
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Abstract
A method for driving a self-scanning light-emitting element array is provided in which two light-emitting elements may be illuminated simultaneously in one chip. In a self-scanning light-emitting element array including a transfer element array and light-emitting element array, a magnitude of the write signal for illuminating adjacent two light-emitting elements simultaneously is two times that of the write signal for illuminating one light-emitting element. The self-scanning light-emitting element array is composed of a plurality of self-scanning light-emitting element array chips arranged in a linear manner, and the two-phase clock pulses are applied commonly to the plurality of self-scanning light-emitting element array chips.
Claims37
A method for driving a self-scanning light-emitting element array including a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- the method comprising the steps of:
- turning on one transfer element, and
- illuminating one light-emitting element corresponding to the turned-on transfer element;
- or
- turning on adjacent two transfer elements simultaneously, and
- illuminating adjacent two light-emitting elements corresponding to the turned-on adjacent two transfer element.
A method for driving a self-scanning light-emitting element array including a self-scanning transfer element array having such a structure that a plurality of three-terminal a transfer elements each having a control electrode for controlling threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- the method comprising the steps of:
- providing a pattern in which an on-state is transferred in adjacent two transfer elements not to illuminate both of adjacent two light-emitting elements corresponding the adjacent two transfer elements, and a pattern in which an on-state is transferred in adjacent two transfer elements to illuminate one of adjacent two light-emitting elements corresponding the turned-on transfer element, and a pattern in which adjacent two transfer elements are turned on simultaneously to illuminate both of adjacent two light-emitting elements corresponding the adjacent two transfer elements simultaneously,
- combining the patterns to illuminate the light-emitting elements.
A self-scanning light-emitting element array comprising:
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- wherein one of two terminals except the control electrode of each of the light-emitting elements is connected to the write signal line through a resistor, respectively.
A self-scanning light-emitting element array chip comprising:
- a first circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- a second circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- and
- one power supply line connected through respective load resistors to respective control electrodes of the transfer elements in the first and second circuits.
A self-scanning light-emitting element array chip comprising:
- a first circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- a second circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- two clock pulse lines connected to each other for applying one phase clock pulse to the first and second circuits;
- two clock pulse lines connected to each other for applying the other phase clock pulse to the first and second circuits;
- and
- one power supply line connected through respective load resistors to respective control electrodes of the transfer elements in the first and second circuits.
A self-scanning light-emitting element array chip comprising:
- a first circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- a second circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a writer signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- and
- one power supply line connected through respective load resistors to respective control electrodes of the transfer elements in the first and second circuits,
- wherein one of the two clock pulse lines is connected through a diode to the control electrode of a transfer element to be first turned on in the first circuit, and
- one of the two clock pulse lines is connected through a diode to the control electrode of a transfer element to be first turned on in the second circuit.
A self-scanning light-emitting element array chip comprising:
- a first circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- a second circuit including,
- a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each transfer element are provided, one phase clock pulse of the two-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the other phase clock pulse of the two-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on, and
- a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a write signal to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- and
- one first clock pulse line for applying one phase clock pulse to the first and second circuits;
- one first current limiting resistor provided in the first clock pulse line,
- one second clock pulse line for applying the other phase clock pulse to the first and second circuits;
- one second current limiting resistor provided in the second clock pulse line,
- a third resistor provided between a terminal of each transfer element and the first or second clock pulse line;
- and
- one power supply line connected through respective load resistors to respective control electrodes of the transfer elements in the first and second circuits.
A method for driving a self-scanning light-emitting element array including a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for a controlling threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, m (m is an integer of 2 or more) clock pulse lines for applying m-phase clock pulses in turn to one of two terminals except the control electrode of each transfer element are provided, one of the m-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and another one of the m-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a current to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- the method comprising a step of:
- precharging each of the clock pulse lines to a predetermined voltage prior to turn on each of the transfer-elements, the predetermined voltage being smaller than Vt which is a voltage of the clock pulse to turn on the transfer element.
A driver circuit for driving a self-scanning light-emitting element array including a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, m (m is an integer of 2 or more) clock pulse lines for applying m-phase clock pulses in turn to one of two terminals except the control electrode of each transfer element are provided, one of the m-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the another one of the m-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a current to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- the driver circuit comprising:
- a first voltage supply for applying a voltage Vt which is a voltage of the clock pulse to turn on the transfer element;
- a second voltage supply for applying a voltage which is smaller than the voltage Vt;
- and
- a switch circuit for setting the voltage of each of the clock pulse lines to the voltage Vt after precharging each of the clock pulse lines to a voltage smaller than the voltage Vt prior to turn on each of the transfer-elements by using the first and second voltage supplies.
A driver circuit for driving a self-scanning light-emitting element array including a self-scanning transfer element array having such a structure that a plurality of three-terminal transfer elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the transfer elements neighbored to each other are connected via electrical means having unidirectional characteristic to a voltage or current, m (m is an integer of 2 or more) clock pulse lines for applying m-phase clock pulses in turn to one of two terminals except the control electrode of each transfer element are provided, one of the m-phase clock pulses causes the threshold voltage or current of the transfer elements in the vicinity of a turned-on transfer element to vary via the electrical means, and the another one of the m-phase clock pulses causes the light-emitting element neighbored to the turned-on transfer element to turn on;
- and a light-emitting element array having such a structure that a plurality of three-terminal light-emitting elements each having a control electrode for controlling a threshold voltage or current are arranged in a linear manner, the control electrodes of the light-emitting element are correspondingly connected to the control electrodes of the transfer elements, and a write signal line for applying a current to one of two terminals except the control electrode of each of the light-emitting elements to be illuminated is provided;
- the driver circuit comprising:
- a voltage supply for applying a voltage Vt which is a voltage of the clock pulse to turn on the transfer element;
- and
- a switch circuit for setting the voltage of each of the clock pulse lines to the voltage Vt after precharging each of the clock pulse lines to a voltage smaller than the voltage Vt prior to turn on each of the transfer-elements by using the voltage supply.
An optical writing head comprising:
- a rod-lens array composed of a plurality of rod-lenses stacked and arranged so as to be geometrically axisymmetric in a thickness direction thereof;
- and
- a light-emitting element array composed of a plurality of light-emitting element array chips arranged in a zigzag manner opposing to the rod-lens array, each light-emitting element array chip including a plurality of light-emitting elements arranged in a linear manner;
- wherein the light-emitting element array chips are arranged in a zigzag manner opposing to two lines which are axisymmetric in the rod-lens array.
An optical writing head comprising:
- a rod-lens array composed of a plurality of rod-lenses stacked and arranged so as to be geometrically axisymmetric in a thickness direction thereof;
- and
- a light-emitting element array composed of a plurality of light-emitting elements arranged in a zigzag manner opposing to the rod-lens array to form two rows of light-emitting elements,
- wherein the light-emitting elements are arranged in a zigzag manner opposing to two lines which are axisymmetric in the rod-lens array.
An optical writing head comprising:
- a rod-lens array composed of first and second sets of rod-lens sub-arrays stacked closely, each set of rod-lens sub-array consisting of a plurality rod-lenses stacked;
- and
- a light-emitting element array composed of a plurality of light-emitting element array chip arranged in a zigzag manner opposing to the rod-lens array, each light-emitting element array including a plurality of light-emitting elements arranged in a linear manner;
- wherein the light-emitting element array chips are arranged in a zigzag manner opposing to two lines which are obtained by moving a longitudinal first center line of the first set of rod-lens sub-array and a longitudinal second center line of the second set of rod-lens sub-array while maintaining the distance therebetween in a thickness direction of the rod-lens array.
An optical writing head comprising:
- a rod-lens array composed of first and second sets of rod-lens sub-arrays stacked closely, each set of rod-lens sub-array consisting of a plurality rod-lenses stacked;
- and
- a light-emitting element array composed of a plurality of light-emitting elements arranged in a zigzag manner opposing to the rod-lens array to form two rows of light-emitting elements,
- wherein the plurality of light-emitting elements are arranged in a zigzag manner opposing to two lines which are obtained by moving a longitudinal first center line of the first set of rod-lens sub-array and a longitudinal second center line of the second set of rod-lens sub-array while maintaining the distance therebetween in a thickness direction of the rod-lens array.
A method for arranging a rod-lens array and a light-emitting element array, comprising the steps of:
- providing a rod-lens array composed of a plurality of rod-lenses stacked and arranged so as to be geometrically axisymmetric in a thickness direction thereof;
- and
- arranging light-emitting element array chips in a zigzag manner opposing to two lines which are axisymmetric in the rod-lens array, each light-emitting element array chip including a plurality of light-emitting elements arranged in a linear manner.
A method for arranging a rod-lens array and a light-emitting element array, comprising the steps of:
- providing a rod-lens array composed of a plurality of rod-lenses stacked and arranged so as to be geometrically axisymmetric in a thickness direction thereof;
- and
- arranging light-emitting elements are arranged in a zigzag manner opposing to two lines which are axisymmetric in the rod-lens array.
A method for arranging a rod-lens array and a light-emitting element array, comprising the steps of:
- providing a rod-lens array composed of first and second sets of rod-lens sub-arrays stacked closely, each set of rod-lens sub-array consisting of a plurality rod-lenses stacked;
- and
- arranging light-emitting element array chips in a zigzag manner opposing to two lines which are obtained by moving a longitudinal first center line of the first set of rod-lens sub-array and a longitudinal second center line of the second set of rod-lens sub-array while maintaining the distance therebetween in a thickness direction of the rod-lens array.
A method for arranging a rod-lens array and a light-emitting element array, comprising the steps of:
- providing a rod-lens array composed of first and second sets of rod-lens sub-arrays stacked closely, each set of rod-lens sub-array consisting of a plurality rod-lenses stacked;
- and
- arranging a plurality of light-emitting elements in a zigzag manner opposing to two lines which are obtained by moving a longitudinal first center line of the first set of rod-lens sub-array and a longitudinal second center line of the second set of rod-lens sub-array while maintaining the distance therebetween in a thickness direction of the rod-lens array.
Dependencies are inferred from the claim text.