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US 7,283,151 B2Granted
Pixel clock generation device causing state transition of pixel clock according to detected state transition and phase data indicating phase shift amount
AssigneeRicoh Company, Ltd.
InventorsYasuhiro Nihei, Masaaki Ishida
Life of this patent
Estimating the term…
Abstract
A transition detection circuit detects a transition of a state of a pixel clock, and outputs a detection signal according to a timing of the detected state transition. A control signal generation circuit generates a control signal according to the detection signal and phase data indicating a transition timing of the pixel clock. A pixel clock control circuit causes the state of the pixel clock to transit according to the control signal.
Claims40
A pixel clock generation device comprising:
- a high-frequency clock generation circuit generating a high-frequency clock;
- a transition detection circuit configured to detect a transition of a state of a pixel clock, and outputting a detection signal according to a timing of the detected transition, the transition detection circuit configured to detect the transition of the state of the pixel clock based on the high-frequency clock generated by the high-frequency clock generation circuit;
- a control signal generation circuit generating a control signal according to said detection signal and phase data indicating a transition timing of said pixel clock;
- and
- a pixel clock control circuit causing the state of said pixel clock to transition according to said control signal.
2 more elements
A pixel clock generation device comprising:
- a high-frequency clock generation part generating a high-frequency clock;
- a clock generation part generating a plurality of clocks having at least one of different phases and different periods according to phase data indicating a phase shift amount of a pixel clock, a status signal indicating a state of said pixel clock, and said high-frequency clock;
- a clock selecting part selecting either of said clocks according to said phase;
- and
- a pixel clock control circuit configured to control the pixel clock to rise when a clock selected by the clock selecting part rises.
2 more elements
A laser scanning device emitting a light beam for scanning a scanned medium by driving a light source according to a pixel clock, the device comprising:
- the light source emitting said light beam;
- a pixel clock generation device including a high-frequency clock generation circuit generating a high-frequency clock, a transition detection circuit configured to detect a transition of a state of a pixel clock, and outputting a detection signal according to a timing of the detected transition, the transition detection circuit configured to detect the transition of the state of the pixel clock based on the high-frequency clock generated by the high-frequency clock generation circuit, a control signal generation circuit generating a control signal according to said detection signal and phase data indicating a transition timing of said pixel clock, and a pixel clock control circuit causing the state of said pixel clock to transition according to said control signal;
- and
- a drive part driving said light source according to said pixel clock output from said pixel clock generation device.
1 more element
A laser scanning device emitting a plurality of light beams for scanning a scanned medium by driving a plurality of light sources according to a pixel clock, the device comprising:
- the light sources emitting said light beams;
- a pixel clock generation device including a high-frequency clock generation circuit generating a high-frequency clock, a transition detection circuit configured to detect a transition of a state of a pixel clock, and outputting a detection signal according to a timing of the detected transition, the transition detection circuit configured to detect the transition of the state of the pixel clock based on the high-frequency clock generated by the high-frequency clock generation circuit, a control signal generation circuit generating a control signal according to said detection signal and phase data indicating a transition timing of said pixel clock, and a pixel clock control circuit causing the state of said pixel clock to transition according to said control signal;
- and
- a drive part driving said light sources according to said pixel clock output from said pixel clock generation device.
1 more element
A laser scanning device emitting a light beam for scanning a scanned medium by driving a light source according to a pixel clock, the device comprising:
- the light source emitting said light beam;
- a pixel clock generation device including a high-frequency clock generation part generating a high-frequency clock, a clock generation part generating a plurality of clocks having at least one of different phases and different periods according to phase data indicating a phase shift amount of a pixel clock, a status signal indicating a state of said pixel clock, and said high-frequency clock, a clock selecting part selecting either of said clocks according to said phase data, and a pixel clock control circuit configured to control the pixel clock to rise when a clock selected by the clock selecting part rises;
- and
- a drive part driving said light source according to said pixel clock output from said pixel clock generation device.
1 more element
A laser scanning device emitting a plurality of light beams for scanning a scanned medium by driving a plurality of light sources according to a pixel clock, the device comprising:
- the light sources emitting said light beams;
- a pixel clock generation device including a high-frequency clock generation part generating a high-frequency clock, a clock generation part generating a plurality of clocks having at least one of different phases and different periods according to phase data indicating a phase shift amount of a pixel clock, a status signal indicating a state of said pixel clock, and said high-frequency clock, a clock selecting part selecting either of said clocks according to said phase data, and a pixel clock control circuit configured to control the pixel clock to rise when a clock selected by the clock selecting part rises;
- and
- a drive part driving said light sources according to said pixel clock output from said pixel clock generation device.
1 more element
An image forming device forming an image on a scanned medium by driving a light source according to a pixel clock, the device comprising:
- a laser scanning device including;
- the light source emitting a light beam for scanning said scanned medium;
- a pixel clock generation device including a high-frequency clock generation circuit generating a high-frequency clock, a transition detection circuit configured to detect a transition of a state of a pixel clock, and outputting a detection signal according to a timing of the detected transition, the transition detection circuit configured to detect the transition of the state of the pixel clock based on the high-frequency clock generated by the high-frequency clock generation circuit, a control signal generation circuit generating a control signal according to said detection signal and phase data indicating a transition timing of said pixel clock, and a pixel clock control circuit causing the state of said pixel clock to transition according to said control signal;
- and
- a drive part driving said light source according to said pixel clock output from said pixel clock generation device.
2 more elements
An image forming device forming an image on a scanned medium by driving a plurality of light sources according to a pixel clock, the device comprising:
- a laser scanning device including:
- the light sources emitting a plurality of light beams for scanning said scanned medium;
- a pixel clock generation device including a high-frequency clock generation circuit generating a high-frequency clock, a transition detection circuit configured to detect a transition of a state of a pixel clock, and outputting a detection signal according to a timing of the detected transition, the transition detection circuit configured to detect the transition of the state of the pixel clock based on the high-frequency clock generated by the high-frequency clock generation circuit, a control signal generation circuit generating a control signal according to said detection signal and phase data indicating a transition timing of said pixel clock, and a pixel clock control circuit causing the state of said pixel clock to transition according to said control signal;
- and
- a drive part driving said light sources according to said pixel clock output from said pixel clock generation device.
2 more elements
An image forming device forming an image on a scanned medium by driving a light source according to a pixel clock, the device comprising:
- a laser scanning device including;
- the light source emitting a light beam for scanning said scanned medium;
- a pixel clock generation device including a high-frequency clock generation part generating a high-frequency clock, a clock generation part generating a plurality of clocks having at least one of different phases and different periods according to phase data indicating a phase shift amount of a pixel clock, a status signal indicating a state of said pixel clock, and said high-frequency clock, a clock selecting part selecting either of said clocks according to said phase data, and a pixel clock control circuit configured to control the pixel clock to rise when a clock selected by the clock selecting part rises;
- and
- a drive part driving said light source according to said pixel clock output from said pixel clock generation device.
2 more elements
An image forming device forming an image on a scanned medium by driving a plurality of light sources according to a pixel clock, the device comprising:
- a laser scanning device including;
- the light sources emitting a plurality of light beams for scanning said scanned medium;
- a pixel clock generation device including a high-frequency clock generation part generating a high-frequency clock, a clock generation part generating a plurality of clocks having at least one of different phases and different periods according to phase data indicating a phase shift amount of a pixel clock, a status signal indicating a state of said pixel clock, and said high-frequency clock, a clock selecting part selecting either of said clocks according to said phase data, and a pixel clock control circuit configured to control the pixel clock to rise when a clock selected by the clock selecting part rises;
- and
- a drive part driving said light sources according to said pixel clock output from said pixel clock generation device.
2 more elements
Dependencies are inferred from the claim text.