Method of transferring information indicating reflecting surface of rotating polygonal mirror
AssigneeCanon Kabushiki Kaisha
InventorsTatsuya Hotogi, Fumiaki Mizuno
Life of this patent
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Abstract
An apparatus has a detection unit, a rotating polygonal mirror and a generation unit. The rotating polygonal mirror has reflecting surfaces and configured to deflect light. The detection unit outputs a first signal in accordance with detecting the light. The generation unit, based on the first signal, generates a second signal which is a main scanning synchronization signal for controlling a write start in a main scanning direction. The second signal has a first waveform and a second waveform. The first waveform does not correspond to a reference reflection surface. The second waveform corresponds to the reference reflection surface and is different to the first waveform.
Claims18
An image forming apparatus comprising:
- a light source;
- a rotating polygonal mirror having a plurality of reflecting surfaces and configured to deflect light outputted from the light source while rotating;
- a detection unit configured to output a first signal in accordance with detecting the light deflected by the rotating polygonal mirror;
- a specification unit configured to specify a reference reflection surface out of the plurality of reflecting surfaces;
- and
- a generation unit configured to, based on the first signal, generate a second signal which is a main scanning synchronization signal for controlling a write start in a main scanning direction, wherein the second signal is a signal having a first waveform that does not correspond to the reference reflection surface and a second waveform which is a waveform that does correspond to the reference reflection surface and is different to the first waveform,
- wherein the generation unit changes, in accordance with the reference reflection surface, a duration from a trailing edge to a rising edge or a rising edge to a trailing edge of a pulse signal which is the second signal, or the generation unit changes, in accordance with the reference reflection surface, a number of pulses of a pulse signal which is the second signal.
An image forming apparatus comprising:
- a first controller configured to transmit a main scanning synchronization signal, and
- a second controller configured to output image data triggered by the main scanning synchronization signal,
- wherein the first controller specifies a reference reflection surface in a plurality of reflecting surfaces that a rotating polygonal mirror comprises, and transmits to the second controller a main scanning synchronization signal having a first waveform that does not correspond to the reference reflection surface and a second waveform which is a waveform that does correspond to the reference reflection surface and is different to the first waveform, and
- wherein the first controller unit changes, in accordance with the reference reflection surface, a duration from a trailing edge to a rising edge or a rising edge to a trailing edge of a pulse signal which is the second signal, or the first controller changes, in accordance with the reference reflection surface, a number of pulses of a pulse signal which is the second signal.
A controller that controls a scanning apparatus having a light source, a plurality of reflecting surfaces, a rotating polygonal mirror that deflects light outputted from the light source while rotating, and a detection unit that outputs a first signal in accordance with detecting the light deflected by the rotating polygonal mirror, the controller comprising:
- a specification unit configured to specify a reference reflection surface out of the plurality of reflecting surfaces;
- and
- a generation unit configured to, based on the first signal, generate a second signal which is a main scanning synchronization signal for controlling a write start in a main scanning direction,
- wherein the second signal is a signal having a first waveform that does not correspond to the reference reflection surface and a second waveform which is a waveform that does correspond to the reference reflection surface and is different to the first waveform, and
- wherein the generation unit changes, in accordance with the reference reflection surface, a duration from a trailing edge to a rising edge or a rising edge to a trailing edge of a pulse signal which is the second signal, or the generation unit changes, in accordance with the reference reflection surface, a number of pulses of a pulse signal which is the second signal.
A controller that generates image data that becomes a basis for an image formed by a scanning apparatus having a light source, a plurality of reflecting surfaces, a rotating polygonal mirror that deflects light outputted from the light source while rotating, and a detection unit that outputs a first signal in accordance with detecting the light deflected by the rotating polygonal mirror, the controller comprising:
- a reception unit configured to receive a second signal, which is a main scanning synchronization signal for controlling a write start in a main scanning direction and which is generated, based on the first signal, in another controller that controls the scanning apparatus by a reference reflection surface out of the plurality of reflecting surfaces being specified, the second signal having a first waveform that does not correspond to the reference reflection surface and a second waveform which is a waveform that does correspond to the reference reflection surface and is different to the first waveform;
- and
- an extraction unit configured to extract information indicating the reference reflection surface from the second signal.
Dependencies are inferred from the claim text.